DE4113695A1 - CONTINUOUSLY OPERATED GAS ANALYZER - Google Patents

CONTINUOUSLY OPERATED GAS ANALYZER

Info

Publication number
DE4113695A1
DE4113695A1 DE4113695A DE4113695A DE4113695A1 DE 4113695 A1 DE4113695 A1 DE 4113695A1 DE 4113695 A DE4113695 A DE 4113695A DE 4113695 A DE4113695 A DE 4113695A DE 4113695 A1 DE4113695 A1 DE 4113695A1
Authority
DE
Germany
Prior art keywords
detector
choke
vacuum
suction device
pressure
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
DE4113695A
Other languages
German (de)
Inventor
Melchior Kahl
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bayer AG
Original Assignee
Bayer AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bayer AG filed Critical Bayer AG
Priority to DE4113695A priority Critical patent/DE4113695A1/en
Priority to AT92106383T priority patent/ATE154133T1/en
Priority to DE59208560T priority patent/DE59208560D1/en
Priority to EP92106383A priority patent/EP0510485B1/en
Priority to US07/869,688 priority patent/US5245857A/en
Priority to CA002066950A priority patent/CA2066950A1/en
Priority to JP04129883A priority patent/JP3138327B2/en
Publication of DE4113695A1 publication Critical patent/DE4113695A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/0004—Gaseous mixtures, e.g. polluted air
    • G01N33/0009—General constructional details of gas analysers, e.g. portable test equipment
    • G01N33/0011—Sample conditioning
    • G01N33/0016—Sample conditioning by regulating a physical variable, e.g. pressure or temperature

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Food Science & Technology (AREA)
  • Medicinal Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Combustion & Propulsion (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Sampling And Sample Adjustment (AREA)
  • Control Of Fluid Pressure (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

The gas analyzer comprises a detector (3) which is dependent upon the mass flow, with a suction device (4) at the detector output. The detector output is connected to a vacuum regulating circuit (6) which maintains the vacuum constant, generated by the suction device (4), at the detector output in relation to the atmospheric pressure. The detector (3) is preceded by a choke (2) in the pipe-line for the gas to be measured. A second choke (11) is connected in parallel, by way of by-pass, to the series arrangement of the first choke (2) and the detector (3). A further (third) choke (1) is connected in advance of the common gas inlet (12, 13). A second vacuum regulating circuit (14) is connected to the common connection point and maintains the pressure constant, prevailing at said connection point, in relation to the atmospheric pressure. The two vacuum regulating circuits (6, 14) each comprise a piezoelectric pressure sensor (18a, 18b), a proportional/Integral controller (20a, 20b) and an electropneumatic control element (21a, 21b).

Description

Die Erfindung geht aus von einem kontinuierlich betriebenen Gasanalysator mit:The invention is based on a continuously operated gas analyzer with:

  • a) einem massenstromabhängigen Detektor,a) a mass flow dependent detector,
  • b) einer Saugvorrichtung am Detektorausgang,b) a suction device at the detector outlet,
  • c) einem am Detektorausgang angeschlossenen Unterdruckregelkreis, der den durch die Saugvorrichtung erzeugten Unterdruck p3 am Detektorausgang gegenüber dem Atmosphärendruck p0 konstant hält,c) a vacuum control circuit connected to the detector output, which keeps the vacuum p 3 generated by the suction device at the detector output constant with respect to the atmospheric pressure p 0 ,
  • d) einer ersten Drossel, die dem Detektor in der Meßgasleitung vorgeschaltet ist,d) a first choke, which is connected upstream of the detector in the sample gas line is
  • e) einer Zweiten Drossel, die der Reihenschaltung von erster Drossel und Detektor als Beipaß parallel geschaltet ist,e) a second choke, the series connection of the first choke and Detector is connected in parallel as a bypass,
  • f) einer dritten Drossel, die dem gemeinsamen Gaseintritt vorgeschaltet ist undf) a third throttle upstream of the common gas inlet and
  • g) einem weiteren Unterdruckregelkreis, der an der gemeinsamen Verbindungs­ stelle der drei Drosseln angeschlossen ist und den dort herrschenden Druck p2 gegenüber dem Atmosphärendruck p0 konstant hält.g) a further vacuum control loop, which is connected to the common connection point of the three throttles and keeps the pressure p 2 there constant with respect to the atmospheric pressure p 0 .

Ein derartiger, mit Unterdruck betriebener und mit Regelkreisen ausgestatteter Gasanalysator ist in DE 29 32 436 beschrieben. Es hat sich jedoch herausgestellt, daß die Unterdruckregelung verbesserungsbedürftig ist, wenn erhöhte Anforde­ rungen an die Meßgenauigkeit gestellt werden.Such a one, operated with negative pressure and equipped with control loops Gas analyzer is described in DE 29 32 436. However, it turned out that the vacuum control is in need of improvement if increased requirements the accuracy of measurement.

Der Erfindung liegt daher die Aufgabe zugrunde, die Regelgenauigkeit bei der Unterdruckregelung im Zusammenhang mit dem vorbeschriebenen kontinuierlich betriebenen Gasanalysator zu verbessern.The invention is therefore based on the object, the control accuracy in the Vacuum control in connection with the above described continuously operated gas analyzer to improve.

Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß die Unterdruckregelkreise jeweils aus einem piezoelektrischen Druckmeßfühler, einem PI-Regler und einem elektropneumatischen Stellglied bestehen.This object is achieved in that the vacuum control loops each consisting of a piezoelectric pressure sensor, a PI controller and a electropneumatic actuator exist.

Durch die Kombination des piezoelektrischen Druckmeßfühlers mit einem PI-Regler und einem elektropneumatischen Stellglied können die Reproduzierbarkeit, die Temperaturabhängigkeit sowie die Langzeitstabitität der Apparatur um ca. eine Zehnerpotenz verbessert werden.By combining the piezoelectric pressure sensor with a PI controller and an electro-pneumatic actuator can Reproducibility, the temperature dependency and the long-term stability of the Equipment can be improved by about a power of ten.

Im folgenden wird ein Ausführungsbeispiel der Erfindung anhand einer Zeichnung beschrieben. Der prinzipielle Aufbau und die Wirkungsweise der Unterdruck­ regelung bei einem kontinuierlich betriebenen Gasanalysator wird in DE 29 32 436 ausführlich erläutert. Auf diese Beschreibung wird ausdrücklich Bezug genommen. Dabei werden für die gleichen bzw. analogen Komponenten gleiche Bezugszeichen verwendet. Der wesentliche Unterschied liegt darin, daß die Unterdruckregelung nicht mit konventionellen Differenzdruckreglern arbeitet, sondern mit speziellen elektronischen Regelkreisen 6, 14. Ein solcher Regelkreis besteht jeweils aus einem piezoelektrischen Drucksensor 18a, 18b, einem Meßverstärker 19a, 19b, einem Proportional-/Integralregler 20a, 20b und einem elektropneumatischen Stellglied 21a, 21b. Mit Hilfe des piezoelektrischen Sensors 18a bzw. 18b wird jeweils der Unterdruck strömungsunabhängig mit einer Genauigkeit von ±0,01 mbar als elek­ trisches Signal erfaßt. Dieses Signal wird durch den Meßverstärker 19a bzw. 19b verstärkt und dem PI-Regler 20a bzw. 20b zugeführt. Die elektrischen Ausgangs­ signale der PI-Regler 20a, 20b wirken direkt auf die elektropneumatischen Stell­ glieder 21a und 21b. Die PI-Regler 20a, 20b führen den Soll-/Istwert-Vergleich durch und erzeugen dementsprechend ein Regelsignal, das die elektropneumatischen Stellglieder 21a, 21b steuert. Aufgrund dieser direkten Ansteuerung wird ein hysteresefreies Regelverhalten und eine Regelgenauigkeit von ±0,01 mbar erreicht. Durch die spezielle Auswahl und Kombination der Regelkreiskomponenten, die be­ sonders gut aufeinander abgestimmt sind, erreicht man eine hohe Langzeitstabilität in einem Temperaturbereich von -10°C bis +70°C. Ein weiterer Vorteil liegt darin, daß über das Regelsignal, d. h. die Abfrage der Stellgrößen, der Meßgasfluß und die Pumpenleistung überwacht werden können, ohne zusätzliche Sensoren oder Durch­ flußmesser im Meßgasstrom zu installieren. Die beschriebene neue Unterdruck­ regelung gewährleistet auch einen luftdruckunabhängigen Betrieb des Gasana­ lysenmeßgerätes, da die beiden Meßfühler als Vergleichsdruck den Luftdruck und damit den gleichen Referenzdruck benutzen.In the following an embodiment of the invention will be described with reference to a drawing. The basic structure and the mode of operation of the vacuum control in a continuously operated gas analyzer is explained in detail in DE 29 32 436. Reference is expressly made to this description. The same reference numerals are used for the same or analog components. The main difference is that the vacuum control does not work with conventional differential pressure controllers, but with special electronic control circuits 6 , 14 . Such a control circuit consists of a piezoelectric pressure sensor 18 a, 18 b, a measuring amplifier 19 a, 19 b, a proportional / integral controller 20 a, 20 b and an electro-pneumatic actuator 21 a, 21 b. With the help of the piezoelectric sensor 18 a or 18 b, the vacuum is detected independently of the flow with an accuracy of ± 0.01 mbar as an electrical signal. This signal is amplified by the measuring amplifier 19 a or 19 b and fed to the PI controller 20 a or 20 b. The electrical output signals of the PI controller 20 a, 20 b act directly on the electropneumatic actuators 21 a and 21 b. The PI controllers 20 a, 20 b carry out the setpoint / actual value comparison and accordingly generate a control signal that controls the electro-pneumatic actuators 21 a, 21 b. Due to this direct control, hysteresis-free control behavior and control accuracy of ± 0.01 mbar is achieved. The special selection and combination of the control loop components, which are particularly well coordinated, ensures high long-term stability in a temperature range from -10 ° C to + 70 ° C. Another advantage is that the control signal, ie the query of the manipulated variables, the sample gas flow and the pump output can be monitored without installing additional sensors or flow meters in the sample gas flow. The new vacuum control described also ensures that the Gasana lysing meter operates independently of the air pressure, since the two sensors use the air pressure and therefore the same reference pressure as the reference pressure.

Die piezoelektrischen Meßfühler und die elektropneumatischen Stellglieder sind handelsübliche Komponenten.The piezoelectric sensors and the electropneumatic actuators are commercially available components.

Claims (1)

Kontinuierlich arbeitender Gasanalysator mit
  • a) einem massenstromabhängigen Detektor (3),
  • b) einer Saugvorrichtung (4) am Detektorausgang,
  • c) einem am Detektorausgang angeschlossenen Unterdruckregelkreis (6), der den durch die Saugvorrichtung (4) erzeugten Unterdruck p3 am Detektorausgang gegenüber dem Atmosphärendruck p0 konstant hält,
  • d) einer ersten Drossel (2), die dem Detektor (3) in der Meßgasleitung vorgeschaltet ist,
  • e) einer Zweiten Drossel (11), die der Reihenschaltung von erster Drossel (2) und Detektor (3) als Beipaß parallel geschaltet ist,
  • f) einer dritten Drossel (1), die dem gemeinsamen Gaseintritt (12, 13) vorgeschaltet ist und
  • g) einem weiteren Unterdruckregelkreis (14), der an der gemeinsamen Ver­ bindungsstelle der drei Drosseln (1, 2, 11) angeschlossen ist und den dort herrschenden Druck p2 gegenüber dem Atmosphärendruck p0 konstant hält, dadurch gekennzeichnet, daß die Unterdruckregelkreise (6, 14) jeweils aus einem piezoelektrischen Druckmeßfühler (18a, 18b), einem PI-Regler (20a, 20b) und einem elektropneumatischen Stellglied (21a, 21b) bestehen.
Continuously working gas analyzer with
  • a) a mass flow-dependent detector ( 3 ),
  • b) a suction device ( 4 ) at the detector outlet,
  • c) a vacuum control circuit ( 6 ) connected to the detector output, which keeps the vacuum p 3 generated by the suction device ( 4 ) constant at the detector output with respect to the atmospheric pressure p 0 ,
  • d) a first throttle ( 2 ) which is connected upstream of the detector ( 3 ) in the sample gas line,
  • e) a second choke ( 11 ) which is connected in parallel with the series connection of the first choke ( 2 ) and detector ( 3 ),
  • f) a third throttle ( 1 ) which is connected upstream of the common gas inlet ( 12 , 13 ) and
  • g) a further vacuum control loop ( 14 ), which is connected to the common connection point of the three throttles ( 1 , 2 , 11 ) and keeps the pressure p 2 there constant with respect to atmospheric pressure p 0 , characterized in that the vacuum control loops ( 6 , 14 ) each consist of a piezoelectric pressure sensor ( 18 a, 18 b), a PI controller ( 20 a, 20 b) and an electropneumatic actuator ( 21 a, 21 b).
DE4113695A 1991-04-26 1991-04-26 CONTINUOUSLY OPERATED GAS ANALYZER Withdrawn DE4113695A1 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
DE4113695A DE4113695A1 (en) 1991-04-26 1991-04-26 CONTINUOUSLY OPERATED GAS ANALYZER
AT92106383T ATE154133T1 (en) 1991-04-26 1992-04-14 CONTINUOUSLY OPERATE GAS ANALYZER
DE59208560T DE59208560D1 (en) 1991-04-26 1992-04-14 Continuously operated gas analyzer
EP92106383A EP0510485B1 (en) 1991-04-26 1992-04-14 Continuous gas analyser
US07/869,688 US5245857A (en) 1991-04-26 1992-04-16 Continuously operated gas analyzer
CA002066950A CA2066950A1 (en) 1991-04-26 1992-04-23 Continuously operated gas analyser
JP04129883A JP3138327B2 (en) 1991-04-26 1992-04-24 Continuous working gas analyzer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE4113695A DE4113695A1 (en) 1991-04-26 1991-04-26 CONTINUOUSLY OPERATED GAS ANALYZER

Publications (1)

Publication Number Publication Date
DE4113695A1 true DE4113695A1 (en) 1992-10-29

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ID=6430436

Family Applications (2)

Application Number Title Priority Date Filing Date
DE4113695A Withdrawn DE4113695A1 (en) 1991-04-26 1991-04-26 CONTINUOUSLY OPERATED GAS ANALYZER
DE59208560T Expired - Fee Related DE59208560D1 (en) 1991-04-26 1992-04-14 Continuously operated gas analyzer

Family Applications After (1)

Application Number Title Priority Date Filing Date
DE59208560T Expired - Fee Related DE59208560D1 (en) 1991-04-26 1992-04-14 Continuously operated gas analyzer

Country Status (6)

Country Link
US (1) US5245857A (en)
EP (1) EP0510485B1 (en)
JP (1) JP3138327B2 (en)
AT (1) ATE154133T1 (en)
CA (1) CA2066950A1 (en)
DE (2) DE4113695A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4231009A1 (en) * 2022-02-21 2023-08-23 Siemens Aktiengesellschaft Pneumatic module for gas analysis device, and manufacturing method and computer program product therefor

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5780717A (en) * 1997-04-23 1998-07-14 Lockheed Martin Energy Research Corporation In-line real time air monitor
FR2789189B1 (en) 1999-02-02 2002-12-13 Air Liquide Sante France METHOD AND INSTALLATION FOR CONTROLLING A MEDICAL VACUUM PRODUCTION PLANT
WO2001004585A1 (en) * 1999-07-12 2001-01-18 Unit Instruments, Inc. Pressure insensitive gas control system
DE102009023224A1 (en) * 2009-05-29 2010-12-02 Avl Emission Test Systems Gmbh Arrangement for the controlled supply and delivery of a gas mixture into an analysis chamber
CN114345090A (en) * 2021-07-27 2022-04-15 赵朋飞 Novel environment-friendly industrial waste gas purifies device

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU466494A1 (en) * 1972-12-21 1975-04-05 Предприятие П/Я М-5539 Device for regulating pressure in a gas-dynamic installation
DE2939957A1 (en) * 1978-10-02 1980-04-10 Du Pont LOW AIR FLOW PERFORMANCE DOSIMETER
DE3010587A1 (en) * 1979-03-19 1980-10-02 Du Pont DOSING KNIFE WITH PUMP OF CONSTANT FLOW
DE2932436A1 (en) * 1979-08-10 1981-02-26 Bayer Ag MASS CURRENT GAS ANALYZER WITH FLOW CONTROL IN VACUUM OPERATION
DE3114119A1 (en) * 1981-04-08 1982-10-21 Kernforschungsanlage Jülich GmbH, 5170 Jülich Control circuit for regulating the pressure in vacuum systems
DE3407552A1 (en) * 1984-03-01 1985-09-05 Bodenseewerk Perkin Elmer Co GAS CONTROL DEVICE FOR CONTROLLING THE FUEL GAS AND OXIDE SUPPLY TO A BURNER IN AN ATOMIC ABSORPTION SPECTROMETER
EP0310210A1 (en) * 1983-03-04 1989-04-05 UTI Instruments Company Measuring trace elements in gas
DE3808982A1 (en) * 1988-03-17 1989-10-05 Ratfisch Instr METHOD AND DEVICE FOR CONTINUOUSLY MEASURING THE HYDROCARBON CONCENTRATION IN A GAS FLOW
DE3822360A1 (en) * 1988-07-01 1990-01-04 Kettrup Antonius Gas sample-taker (sampler)
DE3840322A1 (en) * 1988-11-30 1990-05-31 Hartmann & Braun Ag DEVICE FOR MONITORING THE GAS FLOW IN A GAS ANALYZER AND FOR CORRECTING PRESSURE AND FLOW-RELATED INFLUENCES ON ITS MEASURING SIGNAL

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US4379402A (en) * 1981-01-22 1983-04-12 Beckman Instruments, Inc. Gas analysis instrument having flow rate compensation
DD236991A1 (en) * 1985-05-03 1986-06-25 Elektro App Werke Veb CIRCUIT ARRANGEMENT FOR PIEZORESISTIVE PRESSURE SENSORS WITH CORRECTIVE BEHAVIOR
SU1490132A1 (en) * 1987-04-24 1989-06-30 Днепропетровский химико-технологический институт им.Ф.Э.Дзержинского Apparatus for automatic control of coke gas supply to user

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU466494A1 (en) * 1972-12-21 1975-04-05 Предприятие П/Я М-5539 Device for regulating pressure in a gas-dynamic installation
DE2939957A1 (en) * 1978-10-02 1980-04-10 Du Pont LOW AIR FLOW PERFORMANCE DOSIMETER
DE3010587A1 (en) * 1979-03-19 1980-10-02 Du Pont DOSING KNIFE WITH PUMP OF CONSTANT FLOW
DE2932436A1 (en) * 1979-08-10 1981-02-26 Bayer Ag MASS CURRENT GAS ANALYZER WITH FLOW CONTROL IN VACUUM OPERATION
DE3114119A1 (en) * 1981-04-08 1982-10-21 Kernforschungsanlage Jülich GmbH, 5170 Jülich Control circuit for regulating the pressure in vacuum systems
EP0310210A1 (en) * 1983-03-04 1989-04-05 UTI Instruments Company Measuring trace elements in gas
DE3407552A1 (en) * 1984-03-01 1985-09-05 Bodenseewerk Perkin Elmer Co GAS CONTROL DEVICE FOR CONTROLLING THE FUEL GAS AND OXIDE SUPPLY TO A BURNER IN AN ATOMIC ABSORPTION SPECTROMETER
DE3808982A1 (en) * 1988-03-17 1989-10-05 Ratfisch Instr METHOD AND DEVICE FOR CONTINUOUSLY MEASURING THE HYDROCARBON CONCENTRATION IN A GAS FLOW
DE3822360A1 (en) * 1988-07-01 1990-01-04 Kettrup Antonius Gas sample-taker (sampler)
DE3840322A1 (en) * 1988-11-30 1990-05-31 Hartmann & Braun Ag DEVICE FOR MONITORING THE GAS FLOW IN A GAS ANALYZER AND FOR CORRECTING PRESSURE AND FLOW-RELATED INFLUENCES ON ITS MEASURING SIGNAL

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4231009A1 (en) * 2022-02-21 2023-08-23 Siemens Aktiengesellschaft Pneumatic module for gas analysis device, and manufacturing method and computer program product therefor

Also Published As

Publication number Publication date
EP0510485A3 (en) 1995-12-27
EP0510485A2 (en) 1992-10-28
ATE154133T1 (en) 1997-06-15
DE59208560D1 (en) 1997-07-10
CA2066950A1 (en) 1992-10-27
EP0510485B1 (en) 1997-06-04
US5245857A (en) 1993-09-21
JPH05180826A (en) 1993-07-23
JP3138327B2 (en) 2001-02-26

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